Lions chairman Jason Leonard insists planning for the summer series in South Africa is a "fluid piece of work" because of the coronavirus pandemic.
Both the Lions board and South African Rugby have committed to pressing ahead with the tour in the home of the world champions, although changes to the original itinerary are likely.
A fixture against the Stormers in Cape Town on July 3 is scheduled to launch a quest that culminates in a three-Test series against the Springboks, but the number of cities visited could be significantly reduced.
Leonard refuses to set a deadline for the finalised programme as the hosts contend with the pandemic, the challenges of setting-up biosecure bubbles and the financial implications of potentially playing behind closed doors.
"It's such a fluid piece of work at this moment of time. It's liable to change at the drop of a sixpence really," Leonard said.
"It's moving forward, which is the best position at this moment in time. Even a little while ago, we were more spinning plates than anything else.
"It (the schedule) could change if there's a COVID breakout. We're hoping pretty soon to get it nailed down.
"It's got to be sooner rather than later because we've got announcements of our own to make.
"We're looking forward to the South African Rugby Union to make this tour happen."
All contingency options, including postponement and holding it in the UK, were officially ruled out last week.
"It's always been our position that we want to tour. We're a touring team and that was always our opinion until someone told us otherwise," Leonard said.
"South Africa have already said they can host the tour and want to host us. The fans and the players and people in South Africa have been looking forward to this for 12 years."